Sourkes was a brilliant scientist, internationally known as a pioneer in nutrition, particularly for studies of the role of vitamins in the nervous system and the metabolism of brain neurotransmitters. He was one of the originators of the studies that led to the use of L-DOPA in the treatment of Parkinson's disease, and his introduction of methylDOPA into the pharmacological literature resulted in its widespread use to combat hypertension.
He received the senior award of the Parkinson's Disease Foundation 1963-66, became a fellow of the Royal Society of Canada in 1971 and was honoured with the first Heinz-Lehmann Award in neuropsychopharmacology in 1982.
Esteemed by students and colleagues, he is the author of more than 300 publications, among them a landmark study of the biochemistry of mental disease (1962) and an account of Nobel Prize winners in medicine and physiology. Sourkes was honoured with investiture into the Order of Canada as an Officer in 1993.